Typically, a domestic garden hose has a female end that screws onto the threaded nozzle of a bibcock (faucet), and an opposing threaded male end for attachment of another hose, a valve or some other water device. The ends may be made of plastic or metal.
Most commonly, flow of water into a hose is managed by turning of the bibcock handle and associated valve stem. Some users have found it more convenient to control flow by mounting a ball valve on the bibcock nozzle, and attaching the hose to the ball valve. Flow can then be controlled by turning a lever attached to the ball of the ball valve, which is for many persons an easier way of turning on or off the flow of water. Alternatively, a ball valve may be mounted at the downstream or discharge end of the hose; that makes more convenient the changing of fittings or accessories at the discharge end of the hose. However, having a ball valve at the downstream end usually requires most users to use two hands to operate the valve: one to hold the valve body, the other to rotate the lever and associated ball.
Another limitation of a ball valve as a flow control device relates to the inherent construction of the valve and its size. In particular, since a ball rotates within a socket of a housing, the housing is necessarily larger than the ball. It follows that if, as is desirable, the diameter of the hole through the ball approximates the hose internal diameter, the ball outside diameter and housing dimension are necessarily increasingly larger. When such apparatus at the end of the hose is large and bulky, it can be awkward to handle and prone to damage and catching on shrubbery and the like during use. Alternatively, if the housing, ball and the hole through the ball are all made small, flow is restricted compared to what it desirably would be.
Thus there is a need for an improved flow control valve which is convenient for mounting at either the downstream end of the garden hose or the upstream end. Any valve should be compact in exterior dimensions, durable, and easily turned on and off regardless of whether or not the hose upstream is pressurized, and whether or not there is a flow blocking fitting downstream of the valve.